1. Field of Invention
The present invention relates to an elevating mechanism, more particularly to an elevating mechanism for a projection apparatus.
2. Description of Related Art
FIG. 1 is a projection schematic view of a conventional projection apparatus 50. Referring to FIG. 1, in general, in order to adjust a position of an image from the projection apparatus 50, designers commonly add an elevating mechanism 100 in the projection apparatus 50. The image can be at a proper position on a screen 80 by adjusting a projection angle θ of the projection apparatus 50 via the elevating mechanism 100 for changing a height of the image projected from the projection apparatus 50.
FIG. 2 is an exploded view of the conventional elevating mechanism. Referring to FIG. 2, the conventional elevating mechanism 100 mainly includes a base 110, a movable leg 120, a spring 130, a fixing component 140 and a pad 150. The base 110 is connected with the projection apparatus 50 (as shown in FIG. 1). The movable leg 120 is located in the base 110, and the spring 130 is located between the base 110 and the movable leg 120. Moreover, the fixing component 140 has a positioning section (not shown in the figure), which is suitable for inserting into a positioning groove 122 of the movable leg 120 to fix the movable leg 120. In addition, the pad 150 is located on one end of the movable leg 120.
In the conventional elevating mechanism 100, when a user pushes a button 142 of the fixing component 140 to cause the positioning section of the fixing component 140 to disengage from the positioning groove 122 of the fixing component 140, the movable leg 120 is popped out from the base 110 by an elasticity of the spring 130. The movable leg 120 is fixed by the fixing component 140. Thus, the elevation angle θ of the projection apparatus 50 can be adjusted.
As mentioned above, the spring 130 will provide the elasticity to eject the movable leg 120 from the base 110 quickly, so that the movable leg 120 may impact the base 110 and create noise which is uncomforting to the user, and the elevating mechanism 100 may be likely damaged due to an impact of the movable leg 120 and the base 110. Moreover, it is not easy to control an extrusion length of the movable leg 120 because of a sudden ejecting speed of the movable leg 120, which results in the inconvenience for the user to adjust the projection angle θ. In addition, considering the assembling issue, when the movable leg 120 is ejected from the base 110, it may sway due to the big gap between the movable leg 120 and the base 110. Ultimately, a negative impression regarding a quality of the projection apparatus 50 may be stamped on a mind of the user.